The Hit You Walked Off in High School and the Mood You Can't Shake Now

You remember the play. Maybe it was a helmet-to-helmet collision under the Friday night lights, a hard landing on the mat, or a fender-bender that snapped your head forward before you knew what happened. The world went white and buzzy for a second, your ears rang, and then a coach or a teammate held up a few fingers, you counted them, and you went back in. You walked it off. That was the whole story, or so it seemed. What almost nobody tells you is that the hit you shook off in one afternoon can leave a signature on your mood that shows up years, even decades, later. If you have spent a long time wondering why a low, flat, stubborn heaviness will not lift no matter what you try, the story might actually start on that field.

The bell you rang keeps ringing quietly

When you got your bell rung, the impact did more than make you dizzy for a play. Research following people over long stretches has found that those with a history of a bell-ringing hit are more than three times as likely to experience depression, and that raised risk does not fade quickly. It can persist for years (Beaton et al., 2020, Frontiers in Neurology). This is not about a dramatic diagnosis or anything you can see on a routine scan. It is a quieter, longer tail than most people expect from something they thought they had already put behind them.

Part of why this stays hidden is that the mood shift rarely announces its origin. You do not feel a lingering headache and connect it to a tackle from twenty years ago. You just notice that motivation is thin, that sleep is off, that the version of you your family remembers seems harder to reach. Because the hit itself healed and the ringing stopped, the connection gets lost. To be clear, an old head injury is a risk factor for hard-to-treat depression. It is not a diagnosis by itself, and it is never a reason on its own to reach for any specific treatment. It is simply a clue worth taking seriously.

Why the usual antidepressants can miss it

Here is the part that tends to land hard for former athletes. If your low mood traces back to an old hit, the standard first-line tools may not reach it. Most common antidepressants work primarily on serotonin. That approach helps a great many people, and it is worth trying. But a meta-analysis of antidepressants used after a head impact found no significant difference from placebo (Foreman et al., 2019, J Head Trauma Rehabil). That does not mean you are broken or that nothing works. It suggests that this particular kind of depression can run, at least in part, on a different system than the one most pills are built to adjust.

That system is glutamate, the brain's most common excitatory messenger and a key player in how brain cells form and maintain connections. When the problem sits closer to glutamate signaling than to serotonin, a serotonin-focused medication can be a well-made key for the wrong lock. Understanding that distinction is often the missing piece for people who have quietly cycled through two or three prescriptions and concluded the fault must be theirs.

The other quiet passengers of an old hit

Mood is rarely the only thing that shifts. Athlete concussion depression tends to travel with a cluster of other changes that, taken together, can wear a person down for years without ever pointing back to their cause. Roughly half of people who took a bell-ringing hit are not fully back to baseline years later (TRACK-TBI, 5-year outcomes). Some of the more common quiet passengers include:

• Sleep that never fully resets. Sleep disorders affect roughly 30 to 70 percent of people with a head-injury history, and poor sleep alone can deepen and sustain low mood.
• Subtle hormone changes. Up to about 1 in 6 develop a hormone deficiency after a hit (pooled prevalence near 16.8 percent), which can quietly drive fatigue, low drive, and flat mood.
• A sense of not being back to your old self, a gap between how you function now and how you remember functioning, that others may not see but you feel every day.

None of these prove anything on their own. But if several of them describe you, and they all trace back to a time when you were taking hits, that pattern is exactly the kind of thing worth having a knowledgeable set of eyes examine rather than explain away one symptom at a time.

Why glutamate is part of this conversation

The reason glutamate keeps coming up in newer discussions of hard-to-treat depression is that ketamine and esketamine act on that system rather than on serotonin. Their effects can be measured in hours rather than weeks, and they appear to open a 24 to 72 hour window of heightened neuroplasticity, a period when the brain is more ready to form new connections (Zanos and Gould, 2018, Molecular Psychiatry). Spravato, the esketamine nasal spray, is FDA-approved for treatment-resistant depression. It is not approved for, and is not a treatment for, a concussion or any head injury. The relevance here is narrow and specific: when depression has not responded to standard antidepressants, a glutamate-based option is a different mechanism worth understanding, and an old hit is one reason a person may have landed in that treatment-resistant category in the first place.

A gentler reason to take this seriously

None of this is meant to alarm you. It is meant to give you a fairer explanation than "you just have to live with it." Over the long horizon there are reasons to pay attention to an old head injury with care rather than dread. A national registry found that a history of head injury raised long-term dementia risk by roughly 24 percent (Lancet Psychiatry), and studies have noted elevated odds of death by suicide among people with a concussion history (Erlangsen et al., 2018, JAMA). Those are reasons to be looked at attentively and supported well, not reasons to panic. If your thoughts ever turn dark or toward not wanting to be here, please reach out. You can call or text 988 anytime to reach the Suicide and Crisis Lifeline, and there are people who genuinely want to help you carry this.

The takeaway is simpler than the science. A hit you walked off long ago can still be shaping how you feel today, and if standard care has missed it, that may be because it was looking in the wrong place rather than because you were beyond help. A proper evaluation from a clinic that has neurology on staff can look at this whole picture, your history, your symptoms, and a measured PHQ-9, and help make sense of why the usual approaches came up short. Understanding the why is often the first thing that has felt like solid ground in a long time.